【摘要】 提出采用移动加热器(THM)法在稳态条件下生长碲镉汞晶体的理论模型.该模型利用与时间相关的一维物质扩散方程组,熔区自由边界通过考虑相图来确定,没有考虑对流的影响.给出了x=0.2时碲镉汞晶体生长过程的数值解.结果表明,在生长初始阶段,生成晶体的组分是不均匀的,其长度与生长条件如熔区长度、加热器移动速度、温场分布等因素有关,在初始阶段过后,生成晶体的组分接近多晶料的组分.更多还原

【Abstract】 A theoretical model is presented describing the growth of Hg1-xCdxTe bulk mixed crystals by the travelling heater methed (THM) under steady growth conditions. The model uses the one-dimensional time-dependent equations of species diffusion without convection with the one moving free boundaries of the solution zone determined via consideration of the phase diagram. Numerical solutions are presented for the growth of Hg1-xCdxTe bulk mixed crystals using a feed of x=0.2. The results show that a crystal formed is inhomogeneous in the first growth part. The length of initial transient is determined by growth conditions, such as temperature profile of the solution zone, velocity of the travelling heater and the length of initial solution zone. After that transient the crystal composition approaches that of the feed materials.更多还原